private static void RandomPointsComparer(IPointDComparer comparer)
{
RectD bounds = new RectD(-100, -100, 200, 200);
PointD[] points = GeoAlgorithms.RandomPoints(100, bounds, comparer, 2);
for (int i = 0; i < points.Length; i++)
{
PointD p = points[i];
Assert.IsTrue(bounds.Contains(p));
if (i > 0)
{
Assert.AreEqual(+1, comparer.Compare(p, points[i - 1]));
}
if (i < points.Length - 1)
{
Assert.AreEqual(-1, comparer.Compare(p, points[i + 1]));
}
for (int j = 0; j < points.Length; j++)
{
if (i == j)
{
continue;
}
double distance = p.Subtract(points[j]).LengthSquared;
Assert.GreaterOrEqual(distance, 4);
}
}
}
public void RandomPoints()
{
RectD bounds = new RectD(-100, -100, 200, 200);
PointD[] points = GeoAlgorithms.RandomPoints(100, bounds);
foreach (PointD p in points)
{
Assert.IsTrue(bounds.Contains(p));
}
}
private void DrawConvexHull(PointD[] points)
{
const double radius = 4.0;
// generate new random point set if desired
if (points == null)
{
Size scale = new Size(OutputBox.Width - 4 * radius, OutputBox.Height - 4 * radius);
int count = MersenneTwister.Default.Next(4, 40);
RectD bounds = new RectD(2 * radius, 2 * radius, scale.Width, scale.Height);
points = GeoAlgorithms.RandomPoints(
count, bounds, new PointDComparerY(), 2 * radius);
}
_points = points;
PointD[] polygon = GeoAlgorithms.ConvexHull(points);
OutputBox.Children.Clear();
// draw hull vertices filled, other points hollow
for (int i = 0; i < points.Length; i++)
{
bool isVertex = polygon.Contains(points[i]);
var circle = new Ellipse()
{
Width = 2 * radius, Height = 2 * radius,
Stroke = Brushes.Black,
Fill = isVertex ? Brushes.Black : null
};
Canvas.SetLeft(circle, points[i].X - radius);
Canvas.SetTop(circle, points[i].Y - radius);
OutputBox.Children.Add(circle);
}
// draw edges of convex hull
OutputBox.Children.Add(new Polygon()
{
Points = polygon.ToWpfPoints(),
Stroke = Brushes.Red
});
}
public static GraphManager <PointD> CreateSubdivisionManager(GraphDialog dialog)
{
RectD output = new RectD(0, 0, dialog.OutputBox.Width, dialog.OutputBox.Height);
RectD bounds = new RectD(8, 8, output.Width - 16, output.Height - 16);
PointD[] points = GeoAlgorithms.RandomPoints(40, bounds, new PointDComparerX(), 20);
VoronoiResults results = Voronoi.FindAll(points, output);
Subdivision division = results.ToDelaunySubdivision(output, true);
var manager = new GraphManager <PointD>(dialog, 8);
manager.Graph = division;
manager.Renderer = new GraphRenderer <PointD>(manager);
// scaling factor to keep step costs above node distance
manager._scaleCost = output.Width + output.Height;
return(manager);
}
